Introduction to Planet Earth

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Introduction to Planet Earth Let’s dig a hole to China!

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Introduction to Planet Earth. Let’s dig a hole to China!. Earth Stats. The Earth 's mass is about 5.98 x 10 24 kg. Earth is the densest planet in our Solar System (mass/volume). - PowerPoint PPT Presentation

Transcript of Introduction to Planet Earth

Page 1: Introduction to Planet Earth

Introduction to Planet Earth

Let’s dig a hole to China!

Page 2: Introduction to Planet Earth

Earth Stats

• The Earth's mass is about 5.98 x 1024 kg.

• Earth is the densest planet in our Solar System (mass/volume).

• Earth is made of several layers with different compositions and physical properties, like temperature, density, and the ability to flow.

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The Composition of the Earth

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The Composition of the Earth

Crust• Thinnest layer (5-100 km)• Two types of crust

• Continental • Like granite• Average 30 km

• Oceanic• Like basalt

(Basalt is denser than granite!)• Average 5-8 km

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The Composition of the Earth

Mantle• Extremely Thick! (2,900 km)• It is too far down to drill

• How do we know what it is made of?

• Scientists infer based on:• Pushed up rock• Ocean floor/molten rock

• What is it like?• Like the mineral olivine

• Large amounts of iron and magnesium

www.soc.soton.ac.uk

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The Composition of the Earth

Core• Pretty darn big. (6,856 km)

• (Slightly bigger than Mars!)• 33% mass of the Earth

• Scientists think….• Made mostly of iron• Some nickel, sulfur, oxygen

• What is the evidence?• The particular way seismic

waves travel• Earth’s Magnetic field

N

S

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The Structure

of the Earth

Inner CoreSolid

Outer CoreLiquid

MesosphereSolid

AsthenosphereViscous Liquid

LithosphereSolid

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Asthenosphere = ‘weak sphere’Lower part of Mantle

Lithosphere = ‘rock sphere’Crust and upper rigid part of Mantle

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How HOT is it?

Surface of Sun! 5,500°CSun Core 15,000,000°C

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Convection• Convection (heat) currents

– carry heat from the hot inner mantle to the cooler outer mantle.

• The mantle gets warmer with depth • top of the mantle is ~ 1,600° F (870° C)• bottom of the mantle is ~4,000-6,700° F

(2,200-3,700° C) • The mantle contains most of the mass of

the Earth

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Let’s Make Models of the Earth!

• Inner Core (yellow) diameter 2 cm (4)• Outer core (orange) diameter 6 cm (4)• Mesosphere (red) diameter 11cm (4)• Asthenosphere (brown) diameter 12cm (2)• Lithosphere (sand)

– -after assembly roll edges of asthenosphere in glue and then sand (1.5mM thick)